Jump to content
The Klipsch Audio Community
Sign in to follow this  
MORE KLIPSCH PLEASE

Porting a Chorus ii ?

Recommended Posts

That's right.....porting a Chorus ii.....

I was just surfing the net looking at some pics of Klipsch speaker's.... I came across a guy that got a set of Chorus ii's and the pass rads were all ripped up. So he cut a piece of mdf to fill the area of the pass rad. He then ported them with one large hole. Gave no size of the hole...

 

Has anybody done this here???? Just wondering..... I guess it would work....

 

What's your guys thoughts on this????

 

MKP :-)

  • Like 1

Share this post


Link to post
Share on other sites

My question is what differences are there in cabinet design between the Chorus I and II?  Are they the same except for the passive and port differences?   If so, I can say this...

 

My custom Chorus I's with 4" x 10", dual flared ports absolutely ROCK!!!   I say seal that passive and put some ports in them babies :emotion-21:

port tubes (Medium).jpg

Edited by Matthews
  • Like 1

Share this post


Link to post
Share on other sites

Port modeling for the box is need and the appropriate size back port wall?

Share this post


Link to post
Share on other sites

Ya know Matt when I had both my I's and II's at the house they both hit hard. Now the spec's say that the Chorus ii's go lower..... I don't know if I could tell the difference...

Also my Chorus ii's pass rads have been re-coned.... they are not oem Klipsch re-cones...

Derrick are you saying if the port is in the rear of the box....it would be a different size of the Chorus i's??

Both speakers side by side are the same size....both use the same driver's....now the mid horn is different.....I'm sure there some differences in the x-over's....but they look the same...

MKP :-)

Share this post


Link to post
Share on other sites
Derrick are you saying if the port is in the rear of the box....it would be a different size of the Chorus i's??

 

I seen port size calculators based on the box size and a few other things.  I think one would want to do this compared to just throwing a port in the box.  Port calculations are needed for tuning.  I never done anything like this so, I am asking also.

  • Like 1

Share this post


Link to post
Share on other sites

I believe passive radiator is better, why do you think they went from ports to passives on the Chorus II?

 

Best regards,

John

  • Like 1

Share this post


Link to post
Share on other sites

I believe passive radiator is better, why do you think they went from ports to passives on the Chorus II?

 

Best regards,

John

Like I said my Chorus ii's pass rads have been re-coned.......I think my buddies Chorus ii's had more of a chest thump with oem pass rads.... but it's been 20 years or so since I heard his system... as a note we both have the same amps...Carver TFM-55's

I hear what your saying John..... both my Chorus i's and ii's sound good---well it's been years since I have played my Chorus i's----soon I hope....

MKP :-)

  • Like 1

Share this post


Link to post
Share on other sites

I believe passive radiator is better, why do you think they went from ports to passives on the Chorus II?

 

Best regards,

John

Like I said my Chorus ii's pass rads have been re-coned.......I think my buddies Chorus ii's had more of a chest thump with oem pass rads.... but it's been 20 years or so since I heard his system... as a note we both have the same amps...Carver TFM-55's

I hear what your saying John..... both my Chorus i's and ii's sound good---well it's been years since I have played my Chorus i's----soon I hope....

MKP :-)

you can re tune your passive radiators easily by adding some dead weight to the passive. 2.5 ounces is a good weight. easy to do easy to undo. you will get a substantial increase in available bandwidth. Hope this is of interest. Best regards moray james.

  • Like 1

Share this post


Link to post
Share on other sites

I believe passive radiator is better, why do you think they went from ports to passives on the Chorus II?

Best regards,

John

I have Chorus II's and my roommate blew up my passive radiator so I've had to switch back to ports.

I think the port is a more linear solution when designed properly....thus better sounding.

The problem with a port is the compression you get from air rushing through. This attenuates its output, but also creates a chuffing sound.

The problem with a passive radiator is that it has a suspension, and that suspension has its own non-linearity too.

The port or passive radiator is used to extend low frequency response. This necessitates moving more air than the direct radiator.

In the case of the Chorus II, the active and passive radiator are the same size and have effectively the same excursion capabilities. This isn't really providing more output, at least not as much as is possible from that K48 woofer.

There's more to all this, but at the end of the day I prefer the ported version of my Chorus II's. The ports just need to be bigger than the stock Chorus I.

  • Like 1

Share this post


Link to post
Share on other sites

Yes moray.....the guy that re-coned my pass rads said I might have play with the weights on it...I forget what weight he started with.....just haven't fooled with it.

DrWho.....would love to see a pic of the way you ported the Chorus ii.....and mybe some specs of the size of the port/ports.....

I gotta ask.....how did your roommate blow the pass rad....

Thanks guys....

MKP :-)

Share this post


Link to post
Share on other sites

 

I believe passive radiator is better, why do you think they went from ports to passives on the Chorus II?

 

Best regards,

John

Like I said my Chorus ii's pass rads have been re-coned.......I think my buddies Chorus ii's had more of a chest thump with oem pass rads.... but it's been 20 years or so since I heard his system... as a note we both have the same amps...Carver TFM-55's

I hear what your saying John..... both my Chorus i's and ii's sound good---well it's been years since I have played my Chorus i's----soon I hope....

MKP :-)

 

 

Chest thump is in the 60-70 Hz neighborhood for most people, IIRC, and those are wavelengths of 15-18 ft . . . and those are wavelengths that most rooms wreak havoc with. I'd wager the difference in tactility between them has a lot more to do with room interactions than it has to do with the mass of the passive radiator, and if you want that thump, start by treating the room, moving the speakers, or moving your chair. ;-)

  • Like 2

Share this post


Link to post
Share on other sites

I actually built a new cabinet to get a wider front baffle to make it more Cornwall-like in its presentation. It's an unfinished cabinet, but I'll try to get some pics.

As far as the damage.....

I had my stereo on the main floor in a room that was an addition to the house. My roommate installed a bunch of workout equipment in the basement. Well he decided to turn up the stereo until he could jam out to it in the basement. At the time I was running some EQ to extend the low end a bit, which is totally safe at the levels I listen. The 500W he was using wasn't...The thing I can't believe is he only damaged one of the passives and the active drivers are totally fine.

Right now I'm not using the MF/HF from the Chorus II either. I'm using a BMS driver on a QSC horn (making it a 2 way design with way better polars). At loud levels it's really straining the tweeter, but at the levels I listen it's totally fine.

One other point about the Chorus II....Klipsch voiced the mid-range driver really hot to hit a higher sensitivity spec....which is like turning down the bass EQ knob by a couple clicks. It also doesn't help that the xover has a very reactive impedance at the top end of the sqwauker....I think this is why most prefer a really low output impedance amplifier since it flattens the mid-range response and damps that reactance.

My long term goal is a bigger version of the QSC horn to make the 1kHz xover easier on the tweeter. Maybe even go lower to make things easier on the K48 too. Unfortunately that entails designing my own horn, which is a ton of work to dial in.

Edited by DrWho
  • Like 1

Share this post


Link to post
Share on other sites
My long term goal is a bigger version of the QSC horn to make the 1kHz xover easier on the tweeter. Maybe even go lower to make things easier on the K48 too. Unfortunately that entails designing my own horn, which is a ton of work to dial in.

 

Well I'm sure you could, but you are right about the ton of work. This is why all the tractrix horns out there are just a rework of Dr. Bruce Edgar formulas and construction techniques.

  • Like 1

Share this post


Link to post
Share on other sites

My long term goal is a bigger version of the QSC horn to make the 1kHz xover easier on the tweeter. Maybe even go lower to make things easier on the K48 too. Unfortunately that entails designing my own horn, which is a ton of work to dial in.

 

Grand spirit. Everybody who goes through the work says it was way more work than they knew but they always seem to say it was worth it. I tip my hat.

When you go bigger, the center-to-center has to increase and that can both hose the pattern-matching and tilt your forward lobe. Fiddly bits lie that way--again I tip my hat--you are a braver man than I!

I love this place. It's the biggest bunch of enablers and instigators this side of Audiokarma : )

PS I swear we've all had that roomate once in our lives...sigh.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Sign in to follow this  

×
×
  • Create New...